From: Erez Zadok <ezk@cs.sunysb.edu>
Date: Fri, 24 Sep 2010 06:21:08 +0000 (-0400)
Subject: Unionfs: run check_nd only if nd is valid in ->put_link
X-Git-Url: https://git.fsl.cs.sunysb.edu/?a=commitdiff_plain;h=ab9c9f5d900be70eacb244b39365bda234d38896;p=unionfs-3.14.y.git

Unionfs: run check_nd only if nd is valid in ->put_link

Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
---

diff --git a/fs/unionfs/debug.c b/fs/unionfs/debug.c
index acc44bd70e20..100d2c625c32 100644
--- a/fs/unionfs/debug.c
+++ b/fs/unionfs/debug.c
@@ -438,7 +438,6 @@ void __unionfs_check_nd(const struct nameidata *nd,
 			PRINT_CALLER(fname, fxn, line);
 			pr_debug(" CND1: lower_file of type %s\n",
 				 file->f_path.dentry->d_sb->s_type->name);
-			BUG();
 		}
 	}
 }
diff --git a/fs/unionfs/inode.c b/fs/unionfs/inode.c
index 062163a9e965..4c36f16b4d23 100644
--- a/fs/unionfs/inode.c
+++ b/fs/unionfs/inode.c
@@ -716,6 +716,7 @@ static void unionfs_put_link(struct dentry *dentry, struct nameidata *nd,
 			     void *cookie)
 {
 	struct dentry *parent;
+	char *buf;
 
 	unionfs_read_lock(dentry->d_sb, UNIONFS_SMUTEX_CHILD);
 	parent = unionfs_lock_parent(dentry, UNIONFS_DMUTEX_PARENT);
@@ -726,8 +727,13 @@ static void unionfs_put_link(struct dentry *dentry, struct nameidata *nd,
 		       "unionfs: put_link failed to revalidate dentry\n");
 
 	unionfs_check_dentry(dentry);
+#if 0
+	/* XXX: can't run this check b/c this fxn can receive a poisoned 'nd' PTR */
 	unionfs_check_nd(nd);
-	kfree(nd_get_link(nd));
+#endif
+	buf = nd_get_link(nd);
+	if (!IS_ERR(buf))
+		kfree(buf);
 	unionfs_unlock_dentry(dentry);
 	unionfs_unlock_parent(dentry, parent);
 	unionfs_read_unlock(dentry->d_sb);